"I saw five dead bodies from a car parked behind us, and so far the government has not done enough to save our lives," Qazi Azhar, an Afghan judge, who was caught in the treacherous mountain pass at 3,400 metres, said.
Hamid Karzai, the Afghan president, said he was saddened by the deaths and ordered government workers to do all possible to open the pass.
Abdul Mateen Edraak, the head of Afghanistan's National Disaster and Preparedness Centre, said there had been 17 avalanches reported so far and more than 200 trucks, buses and cars were trapped inside the tunnel, which made the rescue operation more difficult.
Concern was greatest for passengers stuck in cars exposed to the extreme cold, Edraak said.
"Some 50 cars which are exposed to extreme weather are a concern for us but others inside tunnel are not bad," he said.
"The people are stuck there for more than 24 hours and if there are no other avalanches we will hopefully bring them out by end of the day."
Heavy snowfall and rain also caused floods in the south of the country. Zalmay Ayoubi, the spokesman for the governor of southern Kandahar province, said six people had been killed and 10 were missing as a result of floods.